All men dream, but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find that it was vanity: but the dreamers of the day are dangerous menů for they may act their dream with open eyes, to make it possible. -T.E. Lawrence

I read the whole thread and many others.
Too much anecdote and too little fact.

I think we agree that's where we are trying to get to.

I was very specific with Sika and I consider their responses relatively specific (given they have no aviation application). 209 is specific to the acrylic. I am bonding to bare aluminum and steel. 207 does all 3. In the sika chart preparation requires 3 things to bond to all 3;

scuffing, 205 and 207. The rep was helpful in that they provided the specific areas from their marine application data and from their auto-glass references (their tips & tricks). Their conclusion was largely that 210 was not required, and 207 was the preferred solution for using 295UV.

We are where we are because the adhesive qualities appear to be such that some people are being complacent because it works well as there has not been an incident. I am stripping the powder coat off to make sure adhesion is as intended.

The question still remains if we have experience with 207 vs 209.

This isn't meant to be a debate rather a fact finding question (and yes, I understand the irony of that statement).

Most people on the forum are using Sikaflex to bond the canopy or windscreen to the roll bar or canopy frame.

Are you saying that you are using Sikaflex to glue aluminum and steel?

That might explain the disconnect.

For plastic to the steel frames, I've used SIKA PRIMER-209 N.

Hi RV8

sorry if I was not clear. I'm bonding the acrylic to the the bare steel frame, and I thought some had bonded the aluminum skirts to the canopy as well.
In your case I'm assuming you only used 209 because you left on powder coat.

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